Effect of antibacterial treatments and natural chemicals on the quality and safety of marinated raw crab paste during storage at-20°C

The effects of antibacterial treatments and several natural chemicals on the quality and safety of crab paste during storage at -20 degrees C were investigated. All antibacterial treatments significantly reduced the bacterial total viable count (TVC) of swimming crabs, with sodium hypochlorite (NaClO) combined with ultrasonic cleaning having the best effects. Four chemicals significantly inhibited the increase in TVC, pH, and the accumulation of total volatile basic nitrogen (TVB-N) compared to controls, and their combined treatment had synergistic effects. The L- 9(3( 4)) orthogonal experiment showed that the optimum combination was A(1)B(3)C(3)D(2) (i.e., 0.1 g kg(-1) nisin, 0.4 g kg(-1) epsilon-polylysine hydrochloride, 0.3 g kg(-1) tea polyphenol, and 0.5 g kg(-1) citric acid). The TVC, TVB-N concentration, and pH in A(1)B(3)C(3)D(3)-treated samples remained far below the maximum acceptable limit for good-quality marinated, raw, aquatic animal product after 12 months of frozen storage at -20 degrees C. Furthermore, the combined treatment (A(1)B(3)C(3)D(3)) significantly inhibited the reproduction of foodborne pathogenic bacteria and spoilage bacteria. The antibacterial treatments and natural chemicals reduced foodborne pathogenic bacteria and inhibited microbial spoilage, and therefore maintained the quality and safety of crab paste during frozen storage. Antibacterial treatments and natural chemicals could be commercially utilized to maintain the quality and safety of crab paste.